Yes that’s correct.
You are absolutely fine to install and use a single-node Dev licence for the purpose of a PoC. In fact, you can get as many licences as you need for your evaluation.
The move to a commercial licence will come once your evaluation is completed, and you made the decision to deploy Tyk to production environment. Then you will need to obtain a Pro licence for 1, 2 or Unlimited nodes. Also consider how you want to provision any Non-Production environments: Staging, UAT etc.
Finally, don’t forget that any Pro licence also comes with access to our excellent Helpdesk, which has even faster replies than our community site! This could be useful for assisting your PoC
Andrew & the team at Tyk